Why can't ping a wireless broadband modem?

Ace manager gives you the possibility to enter a modem name and domain. (use eairlink as domain, see manual). Because my cellular provider provides me a dynamic ip we use modemname.domain to connect to the modem. ping command gives me an ip address.

I think it’s better not to use an ip address because it’s dynamic.

My problem at the moment is a wireless connection is not possible. But I don’t know why. Is there anyone who was succesfully connected wireless to the wireless modem (raven xt)? Please tell me how you did this.